To assess the effects of maternal obesity, glycemia, lipids, adipokines, and inflammation on infant birth weight, Ravi Retnakaran, MD, of Mount Sinai Hospital in New York City, and colleagues conducted a study involving 472 pregnant women who completed an oral glucose tolerance test but did not have gestational diabetes. One hundred four women had gestational impaired glucose tolerance.

The researchers found that 68 infants were large for their gestational age. Logistic regression analysis identified significant metabolic predictors of having a large-for-gestational-age infant, including pre-pregnancy BMI (odds ratio [OR], 1.16 per 1kg/m² increase); gestational weight gain up to the time of the oral glucose tolerance test (OR, 1.12 per 1kg increase); and leptin level (OR, 0.5 per one standard deviation change). Neither impaired glucose tolerance nor any of the lipid measures were independent predictors of large-for-gestational-age infants.

"These data suggest that maternal weight and its associated circulating factors have a greater impact on infant birth weight than do mild glucose intolerance and lipid levels in women without gestational diabetes," the authors write.